Jenga, this ain't. Hundreds of books carefully stacked, creating what's known as a "tower pile" (tawaa tsumi or タワー積み) in Japanese. Store employees spend thirty minutes—or more—to create these book sculptures that delight some and upset others.

Traditionally, books in Japanese bookstores are stacked in small piles or placed on shelves—like anywhere else. The book tower trend isn't exactly new and puts a flourish on retail presentation, whether it's the straight up "tower pile" or the "spiral pile" variation.

Back in 2009 to mark the launch day of Haruki Murakami's new book 1Q84, Tokyo book retailer Sanseido changed its shop sign to "Books Murakami Haruki" and unveiled a book tower that was then copied by other stores. Now, it seems there are even manga towers and spirals—but don't think every bookstore does this.

"I live in Tokyo, and I've never seen books stacked like this at a book store," a commenter wrote on 2ch, earlier this spring. (Note: I live in Osaka and haven't seen any ridiculous book towers, either.) However, this is a thing—the question always becomes how widespread of a thing.

On 2ch, Japan's largest online forum, some are saying retailers should not play with merchandise like this and are calling this sort of display a marketing stunt—which is exactly what it is. These retailers hope that the photos will circulate online and, well, get their shop's name out there. That's why some of these photos were actually tweeted out by retailers themselves. Guess it's working!

These book towers and spirals might be good for publicity, but they're not good for the actual books. First, lying books flat on top of each other can apparently damage the spines—especially, the books at the bottom of the stacks. Stacking can put pressure on the books, warping the pages. See the below image, which depicts the results of simple stacking:

Then, there's the fact that the tower and spirals put uneven pressure on the books, which compounds the problem. "I buy books through Amazon, so whatever," quipped one 2ch user.

On Twitter, however, many people in Japan do seem to think the book towers are amazing. And, marketing stunt aside, they are. But you can see how the precariously tall towers and spirals might be damaging the books. Have a look for yourself: